docs: def nodes_dump(self):
          """Dump the entire contents of the nodes table."""
          self._flush_nodes()
          for (graph, node, branch, turn,tick, extant) in self.sql('nodes_dump'):
              yield (
                  self.unpack(graph),
                  self.unpack(node),
                  branch,
                  turn,
                  tick,
                  bool(extant)
              )